Black Diamond Mines Regional Park

Hike Host: Troy H.

From the 1860s through the turn of the last century, five coal mining towns thrived in the Black Diamond area: Nortonville, Somersville, Stewartville, West Hartley, and Judsonville. As the location of California’s largest coal mining operation, nearly four million tons of coal (“black diamonds”) were removed from the earth. From the mid-1920s to the mid-1940s, the Hazel-Atlas Mine produced silica sand to make jars, bottles, and other glass items.

Although little remains of the mining communities, we will visit a few mine entrances and pass through a historic cemetery that serves as a monument to the lives of the former residents.

On this day the park is holding an open house, and all the underground mine tours are free of charge with no pre-registration required.  After the hike, those wanting to explore further can take the approx. ¾ mile tour underground. Hardhats and flashlights provided by the park.

An old cemetery and exploring underground.  Perfect for the week before Halloween.

The Hike

We will start out on the Stewartville Trail and the Pittsburg Mine Trail to the Hazel Atlas Mine Portal.  We can explore inside after the hike. We continue up trails carved in sandstone to another mine entrance and a small excavation we can enter called the Powder Magazine. We will have our meeting early in the hike up on Ridge Trail with a view overlooking Stewartville Valley and beyond to Mount Diablo.

After the meeting we hike part of Chaparral Loop Trail, Upper Manhattan Canyon Trail and Black Diamond Trail to Rose Hill Cemetery. Spend some time reading the details on the historic grave markers if you like. Then we will complete Manhattan Canyon and Chaparral Loop trail which will lead us to the Greathouse Visitor Center which is located in an underground chamber. This completes the hike. Here, those that want to can take the underground mine tour or continue on the paved path back to the parking lot.

Difficulty: Level 3 Challenging | Miles: 5.25 | Elevation: 960′ ft

Getting There

(click for directions)

From San Jose take I-680 North. In Concord stay right & take Hwy 242 to Hwy 4 East toward Antioch. Take the Somersville Rd Exit. Drive South on Somersville Rd to the park entrance. We will meet at the parking lot at the end of the road.

Know Before you go

Parking $5 – Dogs OK w/$2 fee (no dogs on mine tours)